Abstract: In a lithographic projection apparatus, a time-saving height measurement method is used. While in a projection station (105,108,111) the pattern of a mask (129) is projected on the fields of a first substrate (120), the height of the fields of a second substrate (121) is measured in a measuring station (133). In the measuring station, the height of the substrate fields and the height of the substrate holder (113) are measured by a first height sensor (150) and a second height sensor (160), respectively, and the value of the height of the substrate holder associated with the ideal height of the substrate field is determined for each substrate field. In the projection station, only the height of the substrate holder (111) is controlled by a third height sensor (180). The second and third height sensors are preferably part of a composite XY interferometer system extended with a Z measuring axis.

Abstract: An alignment device, for use in a lithographic apparatus, for aligning a first object, provided with a first alignment mark relative to a second object, provided with a second alignment mark, employs as a radiation source a laser which emits an alignment beam having a wavelength which is of the order of 1000 nm and to the order of 1100 nm.

Abstract: Support device (53) provided with a first part (69) and a second part (71) which is supported relative to the first part by means of a gas spring (73) having a pressure chamber (75). A gas supply (117), which compensates for gas leakage from the pressure chamber (75) during operation, is connected to an intermediate space (119) which is in communication with the pressure chamber (75) via a pneumatic restriction (121). The gas pressure present in the intermediate space (119) is held as constant as possible during operation by means of a control loop (123), to prevent transmission of pressure fluctuations which are present in the gas supply (117) to the pressure chamber (75) as much as possible. Such pressure fluctuations are undesirable in the pressure chamber because they cause mechanical vibrations in the second part of the support device and the device to be supported.

Abstract: In an interferometer system, variations of the refractive index in the medium traversed by the measuring beam (123) can be detected by using two measuring beams (123, 125) having wavelengths which differ by a factor of three. For this choice of the wavelength ratio, the interference filters of the polarization elements, such as the beam splitter (127), the .lambda./4 plates (130, 131) and the antireflection coatings can be manufactured relatively easily, and the detection accuracy is increased.

Abstract: A lithographic projection apparatus for step-and-scan imaging of a mask pattern (c) on a substrate (W) is described. The synchronous movement of the mast (MA) and the substrate (W) during scanning is controlled by means of contactless measuring systems, inter alia, interferometer systems (ISR, ISW), while the measuring faces (R.sub.1,r, R.sub.1,w) associated with these systems are formed by faces of the holders (WH, MH) for the substrate (W) and the mask (MA), so that very accurate measurements are possible.

Abstract: Photolithographic apparatus (1) including an illumination unit (3). The illumination unit (3) comprises, in this order, a radiation source unit (11), a first optical system (5) and an optical waveguide (17). The apparatus (1) further includes a second optical system (7) and a mask table (9). The apparatus (1) is adapted in such a way that both the stepper mode and the scanner mode are selectable modi, and comprises means by which the illumination unit (11), when being operative, has a slit-shaped static illumination field with a width s which is variable between s.sub.min and s.sub.max while substantially maintaining energy within the static illumination field.

Abstract: A positioning device is disclosed. The positioning device has a first part and a second part, the second part further has an object table. The second part may be displaced relative to the first part parallel to the XY-plane and may be rotated about the Z-axis by means of three motors. The motors are Lorentz type motors having a permanent magnet system and an electrical coil system cooperating therewith. The electrical coil systems each have windings which are substantially directed parallel to a main axis of the electrical coil system and perpendicular to the Z-axis. According to the invention, the main axis of each of the three motors encloses an angle of substantially 120.degree. with the main axis of each of the two other motors.

Abstract: Illumination unit (2) for an optical system, including an illumination system (1) which comprises, in this order, a radiation source (3) and a first optical integrator (11). The illumination unit (2) further comprises a detection system (45) including a radiation-sensitive detector (47). The illumination system (1) comprises a second optical integrator (13). The two integrators (11, 13) enclose a prism system (15) comprising at least one prism (17). The prism system (15) has a coupling-out surface via which light can be coupled out of the illumination system (1), and an exit surface via which light can be coupled out of the prism system (15), without the intensity in the main light path being essentially influenced. The detection system (45) is arranged proximate to the exit surface of the prism system (15) and comprises light-integrating means.

Abstract: A composite interferometer system has a plurality of X and/or Y measuring axes which co-operate with an X and/or Y measuring mirror arranged on an object. The interferometer system also has at least one Z measuring axis, which extends partly in an XY plane and co-operates with Z measuring mirrors arranged on the object and Z reflectors. Thus, a larger number of more accurate and reliable measurements can be performed with the interferometer system.

Abstract: Two-dimensionally balanced positioning device with two object holders, and lithographic device provided with such a positioning device.A positioning device (3, 97, 179) with a first displacement unit (25, 189) for displacing a first object holder (11, 181) and a second displacement unit (27, 191) for displacing a second object holder (13, 183). The object holders can be displaced by the positioning device alternately from a measuring position into an operational position and can be displaced by the respective displacement units independently of one another in the measuring position and in the operational position.The displacement units are provided with force actuators which each have a first part (47, 49; 117, 119; 215, 217) which is coupled to the relevant object holder and which is displaceable under the influence of a driving force relative to a second part (59, 61; 133, 135, 137, 139; 219, 221) which is fastened to a balancing unit (69, 149, 205) which is common to the two displacement units.

Abstract: A scanning-slit exposure device is provided with a radiation source (1) emitting radiation pulses through an exit window (2). An imaging system (3) images the exit window onto a surface (4) to be exposed by the radiation. The surface is scanned relative to the exit window image in a scan direction. To avoid the banding-type non-uniformities in the exposure, the device comprises a scattering element (12) which scattering element causes a blur of the exit window image only in the scan direction. The scattering element is arranged in the entrance pupil of the imaging system (3).

Abstract: A method is described for repetitively imaging a mask pattern, on separate fields of a substrate (W), for example, for IC manufacture, which substrate fields are positioned without any field-by-field alignment so that the speed of throughput of substrates can be increased. An accurate interferometer system (50, 100, 150) having five measuring axes (MAX.sub.1, MAX.sub.2, MAX.sub.3, MAX.sub.4, MAX.sub.5) is also described, which system is intended in the first instance for use in an apparatus for performing the method, but which can also be used in a more general way in those cases where an object must be measured in five degrees of freedom.

Abstract: A high-quality lens system (PL) is described, which system is rinsed with a gas having a low refractive index so as to reduce the influence of variations of ambient parameters on the optical behaviour. By adding a very small quantity of ozone to this gas, it is prevented that any deposit will be produced on the lens elements within the lens holder (PLH) as a result of decomposition of organic particles caused by UV radiation and precipitation of the decomposition products.

Abstract: An imaging apparatus and an illumination unit for use in such an apparatus are described, which unit comprises an illumination housing (LH) accommodating a radiation source (LA) and at least a reflector (RL). To prevent a decrease of the radiation power supplied by the illumination housing, this housing is provided with means (LA, SH, L.sub.29) which prevent a diffuse deposit of silicon-containing particles present in the ambient air from being formed on optical components within the illumination housing.

Abstract: An apparatus for projecting a mask pattern (MA) on a substrate (W) by means of a projection lens system (PL) is described, which apparatus comprises a device for aligning a mask alignment mark (M.sub.1, M.sub.2) with respect to a substrate alignment mark (P.sub.1, P.sub.2). Means (WE.sub.1, WE.sub.2) preventing phase differences due to reflections at the mask plate (MA) from occurring within the alignment beam portions received by a detection system (13, 13') are arranged in the path of selected alignment beam portions (b.sub.1, b.sub.1 ').

Abstract: A projection apparatus is described having a reference plate with a set of grating marks in X and Y directions for aligning with an exposure mask having similar marks, and having four detectors for each mark, and having a lens system for projecting only the relevant mark on the relevant detector. A method of projecting is also described in which the detection signals are simultaneously processed with other signals to result in a control signal to adjust image quality.

Abstract: An apparatus for projecting a mask pattern (MA) on a substrate (W) by means of a projection lens system (PL) is described, which apparatus comprises a device for aligning a substrate alignment mark (P.sub.1 ; P.sub.2) with respect to a mask alignment mark (M.sub.1 ; M.sub.2), the projection lens system (PL) forming part of the alignment device. A correction element (25) is arranged in this system (PL) to compensate for the fact that this system (PL) is not optimized for the wavelength of the alignment beam (b).

Abstract: A method and an arrangement for aligning relative to each other a mask pattern (C) and a substrate (W) which are both provided with two alignment marks wherein by using two separate alignment systems (AS.sub.1, AS.sub.2) which are each associated with one mask mark (M.sub.1, M.sub.2) and which are each used for aligning the substrate marks (P.sub.1, P.sub.2) relative to said mask marks the substrate (W) and the mask (M) can be aligned accurately without referring to the frame of the exposure apparatus and in addition it is possible to detect magnification errors.

Abstract: A positioning device for manipulation of objects, provided with an object holder (5) which is rotatable about an axis of rotation (.theta.) by means of a .theta.-manipulator and is displaceable by translation along a Z-axis coinciding with the axis of rotation (.theta.) by means of a Z-manipulator. The two manipulators are coupled to each other by means of a separator (17, 153) in such a manner that the .theta.-movement and the Z-movement are independent of each other. The positioning device is particularly suitable for manipulation of objects in the submicron range, such as takes place, for example, in optical lithographic devices according to the invention.